In the Shadow of the Moon: The Science, Magic, and Mystery of Solar Eclipses

By Anthony Aveni

Anthony Aveni, Yale University Press, 2017; 312 pages; $28.00

You’ve already made plans to view the August 21 solar eclipse from inside the path of totality, right? If not, this is an ungentle second reminder from your erstwhile astronomer not to miss an event that should be on everyone’s bucket list [See Sun, Moon, Earth by Tyler Nordgren, “Bookshelf,” 11/16]. Whether you go, however, Anthony Aveni’s panoramic look at the history and culture of solar eclipses is a recommended way to share the spirit of the occasion. Aveni, professor of astronomy and anthropology at Colgate University, is a seminal figure in the field of cultural astronomy, the study of alignments of ancient buildings and writings of early civilizations to reveal what our ancestors knew about the heavens and how they conceived of cosmic order. He is also a prolific writer and an engaging raconteur.

Eclipses of both the Sun and the Moon are such startling occurrences that they were recorded by almost every literate culture. Early Babylonians kept systematic chronicles on clay tablets, and ancient Greeks developed clockwork mechanisms to predict them. Chinese astrologers, as early as the third millennium bce, were charged with advising the emperor on cosmic matters, and reputedly could be hanged for failing to anticipate a solar eclipse. The Dresden Codex, one of the few surviving documents of pre-Columbian Mayan civilization, contains hieroglyphs representing a serpent eating the Sun, and numeric inscriptions that seem to indicate a knowledge of the repeating cycle of solar eclipses. Maya astronomers, interestingly, may have been trying to predict not only future eclipses, but also, according to Aveni, “to project eclipse calculations millennia backward in mythic time to the previous Maya creation era, the one that ended in 3114 BCE.”

As late as the seventeenth century, solar eclipses inspired reactions of shock and awe, with broadsides prophesying plagues and floods to follow an eclipse visible in London in 1652. But times were changing, and veni provides many a rousing (and seldom-heard) story of eclipses observed in the name of modern science. Closest to home is the eclipse of January 24, 1925, when the edge of the Moon’s shadow brushed the island of Manhattan. Astronomers conscripted legions of volunteer observers to stand at street corners north to south and to report whether they experienced totality. The project, to update precise values of the size of the Moon from the extent of its shadow, met with remarkable success—an observer at 240 Riverside Drive saw a brief second of darkness, while another, just 225 feet further south at 130 Riverside Drive, glimpsed only a tiny sliver of the Sun.

It isn’t so easy at most eclipses, which tend to require elaborate preparation and travel to exotic locations. Typical was the experience of Warren De la Rue, in the era of wet photographic plates, who transported heavy cameras and a complete darkroom to Spain in July 1860. During three minutes of totality, he managed, by dint of remarkable effort, to obtain forty exposures. “If a future opportunity ever presented itself for my observing a total solar eclipse,” he confessed, “I would give up all idea of making astronomical observations, and devote myself to that full enjoyment of the spectacle which can only be obtained by the mere gazer.” Good advice for all of us this coming August 21!